The residents of the northern English constituency of Makerfield are going to the polls on Thursday. The by-election is a key one that could pave the way for the next time Greater Manchester Combined Authority‘s current mayor, Andy Burnham, may be able to make a comeback to the UK Parliament.

The resignation of a Labour colleague caused the election to be called, thus bringing much unexpected attention to the former coal mining region. The poll is seen as the tipping point in an expected challenge on leadership of the unpopular Prime Minister Keir Starmer.

Burnham’s triumph would be akin to a starting gun in a bid to replace Starmer as Labour leader. Burnham’s win would kick off the process to replace Starmer as Labour leader, if he managed to beat the Reform UK candidate from the populist party, Robert Kenyon. Such a change would make this Britain’s seventh new prime minister in less than 11 years, but Starmer has made it clear that he’ll stand up for himself should he face a threat.

Burnham, 56, has been two times before in the race for the Labour leadership, both in 2010 and in 2015, but has failed. In recent weeks, he has worked hard to denigrate the idea of his nationhood, saying the by-election is more about “improving the lives of people living in the area where he’s lived and where he raised his kids.

Although his localism is his focus, most of the interest is paid to the signs of how he’ll rule the whole country. But the opposition contenders have suggested Burnham’s use of Makerfield was only to take control of the country.

In a speech on X late Wednesday, Burnham said that change is definitely happening. He put his bid for office in terms of a rejection of the four-decade-long “trickle down” approach that had not helped the local community.

Labour is confident of Burnham’s prospects after sending “big guns” to the district and dozens of MPs. Burnham is ahead by a lead that is now in the balance in the polls but Reform is coming in close behind. Official results are due in the early hours of Friday morning, but the vote share of Reform has been hit by the formation of a new right-wing party, Restore Britain.

Burnham has suggested that he’ll run against the 63-year-old prime minister, but may not do so right away. But it looks like former health minister Wes Streeting is ready to put a challenge out there on his own, if Starmer does not do it, or can’t quite follow through.

But Starmer, who led Labour to a historic landslide victory in 2024 following a crushing defeat at the previous election in 2019, says he will fight any leadership challenge. The prime minister said he’s always been a “man against the odds” and is a man who will fight back once again.

But several senior Labour lawmakers who have spoken with Starmer think he might be won over to peacefully give up the reins. Burnham has considerable backing in the Labour party among MPs, and an uncontested leadership change won’t leave MPs with a months-long leadership battle to play out in the summer.

In order to facilitate a smooth transition, lawmakers say Burnham could offer Streeting a prominent cabinet job if he cooperates. But party sources say a speedy, clean solution is critical if they are not to lose out on the support of voters at the next national election, scheduled for 2029.